检索结果-南通市图书馆

The effect of gas phase polydimethylsiloxane surface treatment of metallic aluminum particles： Surface characterization and flow behavior

在线全文

学校读者我要写书评

暂无评论

Particuology 2017年第1期15卷 92-101页

作者： Bellamarie Ludwia jennifer L. Gray Applied Research Laboratory The Pennsylvania State University North Atherton Street State College PA 16801 USA Materials Research Institute The Pennsylvania State University USA

Aluminum particles were exposed to gaseous polydimethylsiloxane （PDMS） to produce a hydropho- bic surface coating for enhanced flow and fluidity. Surface retention of the intact PDMS was confirmed through infrared and X-ray photoelectron spectroscopy. Transmission electron microscopy was used to image cross-sections of the treated particles and energy dispersive spectroscopy element maps demon- strated the presence of a surface layer consisting of silicon and oxygen. Density measurements provided evidence for improvements in the Hausner ratio and Carr index of the PDMS-treated aluminum, indicating a reduction in inter-particulate cohesion through increased bulk density. Stability, compressibility, shear, aeration, and permeability of the particles were assessed by powder rheometer. The compressibility was reduced by approximately 32% following surface treatment, revealing a reduction in void space, while Mohr＇s circle analysis and shear testing determined that the extrapolated cohesion value was reduced by approximately 53% and the flow factor at 6 kPa was doubled. Aeration testing showed that the air velocity required to obtain a fluidized bed was on the order of 0.35 mm/s for the treated powder, whereas the raw powder could not be uniformly fluidized. PDMS may be a viable option for the large-scale treatment of aluminum powder for flow applications.

关键词： Aluminum powder Polydimethylsiloxane X-ray photoelectron spectroscopy Diffuse reflectance infrared Fourier transform spectroscopy Flowability FT4 powder rheometer

To name or not to name？ An overview of the social and ethical issues raised by removing anonymity from sperm donors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2010年第6期12卷 801-806页

作者： jennifer A. Burr University of Sheffield School of Health and Related Research SheffieM SA 1 4DA UK

The aim of this paper is to focus on the ethical issues raised by the removal of anonymity from sperm donors. The increasing currency of a ＇right to genetic truth＇ is clearly visible in the drive to revise the legislation on donor anonymity in Western and European countries. The ethical debate is polarized between the ＇right to privacy＇ of the donor or parent and the ＇right to know＇ of the prospective child. However, it is evident that religious, social and cultural attitudes have an overarching impact on attitudes towards sperm donation generally and anonymity specifically. In Asian countries, the social and cultural heritage is hugely diverse and different from those of the West. This review considers the research exploring the complexity of ethical issues informing this debate, and argues that parent＇s decisions to reveal donor insemination origins to their children are highly complex and relate to a range of social and cultural attitudes that have not been addressed within the policy to remove anonymity from sperm donors.

关键词： anonymity ethics disclosure genetic origins secrecy sperm donation

Adsorption kinetics of the herbicide safeners,benoxacor and furilazole,to activated carbon and agricultural soils

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2020年第3期32卷 23-34页

作者： Saraswati Poudel Acharya Jacob Johnson jennifer Weidhaas Civil and Environmental Engineering University of UtahSalt Lake CityUTUSA Center for Science and Mathematics Education University of Utah155 South 1452 EastSalt Lake CityUT 84112USA

Chloroacetamide herbicides,namely acetochlor and metolachlor,are common herbicides used on corn and soybean *** safeners,namely benoxacor and furilazole,are commonly used in formulations containing chloroacetamide *** reports on adsorption of chloroacetamide herbicides are available,yet little information exists regarding adsorption potential of co-applied ***,the adsorption and desorption characteristics of selected herbicide safeners to granular activated carbon(GAC) and in agricultural soils are ***,soil column studies were performed to understand the leaching behaviour of the herbicide Dual II *** sorption experiments of safeners to three agricultural soils and one GAC showed that adsorption was best fitted by the Freundlich *** Freundlich adsorption constant,kf,for benoxacor and furilazole sorption onto three agricultural soils ranged from0.1 to 0.27 and 0.1 to 0.13(mg/g) x(mg/L)(1/n),*** kf for benoxacor and furilazole to GAC was 6.4 and 3.4(mg/g) x(mg/L)(1/n),respectively,suggesting more favorable sorption of benoxacor to GAC than furilazole to *** sorption to soils was reversible as almost 40%-90% of both safeners was desorbed from three *** results were validated in four replicated soil column studies,where S-metolachlor was shown to leach similarly to the safener benoxacor,originating from the herbicide *** leaching of S-metolachlor and benoxacor was influenced by soil ***,these results show that safeners will move through the environment to surface waters similarly to the active ingredients in herbicides,but may be removed during drinking water treatment via GAC.

关键词： Herbicide safener Dual Ⅱ magnum Adsorption Granular activated carbon Soil column transport

Data-driven analysis of process,structure,and properties of additively manufactured Inconel 718 thin walls

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1168-1182页

作者： Lichao Fang Lin Cheng jennifer A.Glerum jennifer Bennett Jian Cao Gregory J.Wagner Department of Mechanical Engineering Northwestern UniversityEvanstonIL60208USA Department of Materials Science and Engineering Northwestern UniversityEvanstonIL60208USA DMG MORI Hoffman EstatesIL60192USA Department of Mechanical and Materials Engineering Worcester Polytechnic InstituteWorcesterMA01609USA Department of Civil and Mechanical Engineering US Military Acadeemy at West PointWest PointNY10996USA

In additive manufacturing of metal parts,the ability to accurately predict the extremely variable temperature field in detail,and relate it quantitatively to structure and properties,is a key step in predicting part performance and optimizing process *** this work,a finite element simulation of the directed energy deposition(DED)process is used to predict the space-and time-dependent temperature field during the multi-layer build process for Inconel 718 *** thermal model results show good agreement with dynamic infrared images captured in situ during the DED *** relationship between predicted cooling rate,microstructural features,and mechanical properties is examined,and cooling rate alone is found to be insufficient in giving quantitative property *** machine learning offers an efficient way to identify important features from series data,we apply a 1D convolutional neural network data-driven framework to automatically extract the dominant predictive features from simulated temperature *** good predictions of material properties,especially ultimate tensile strength,are obtained using simulated thermal history *** further interpret the convolutional neural network predictions,we visualize the extracted features produced on each convolutional layer and compare the convolutional neural network detected features of thermal histories for high and low ultimate tensile strength cases.A key result is the determination that thermal histories in both high and moderate temperature regimes affect material properties.

关键词： Inconel process additive

A surface-based hiding function linking flume and field data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2017年第10期60卷 1560-1569页

作者： ZHANG LiGuo FU XuDong DUAN jennifer G State key Laboratory of Hydroscience and Engineering Tsinghua University Department of Civil Engineering and Engineering Mechanics University of Arizona

The quantification of the sheltering and exposure effects of non-uniform sediments has been widely achieved through hiding function models. Big challenge exists so far in the model parameter that is highly variable and differs greatly between laboratory flumes and field streams. This paper presents an improved surface-based hiding fimction. The force balance for particle inception was formulated and the allocation of the overall bed shear stress into each group of sediments was mimicked. The new hiding function was examined against and agrees well with the documented field and flume data. It was shown that the hiding fimction is closely related to the relative flow depth and the reference elevation in the velocity profile in addition to the bed material gradation. The power law of velocity profile that applies to both flume flows and natural streams can link the flume and field data together. The hiding function with b = 1/6 and b = 1/2 is applicable to natural streams and laboratory flumes, respectively. The value orb = 0.263 also works well for gravel bed rivers. The range of the reference elevation, namely z0 = 0.4Dm-1.4Dm, is recommended for either the flume or field data. The new hiding function contributes to addressing clearer physical meanings and a useful perspective for further improvement.

关键词： hiding function relative flow depth flume and field data reference elevation

Hypoxia inducible factor in hepatocellular carcinoma:A therapeutic target

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2015年第42期21卷 12171-12178页

作者： Daniel Lin jennifer Wu Fellow Hematology and Medical Oncology Program NYU School of Medicine Perlmutter Cancer Center NYU Langone Medical Center Division of Hematology and Oncology NYU School of Medicine Subdivision of GI Oncology Perlmutter Cancer Center NYU Langone Medical Center Division of Hematology and Oncology

Hepatocellular carcinoma(HCC) is one of the most commonly diagnosed and deadly cancers worldwide; its incidence has been rising in the United States due to the increase in hepatitis C associated cirrhosis and the growing epidemic of obesity. There have been no effective therapeutic options in the advanced disease setting beyond sorafenib, a multi-targeted tyrosine kinase inhibitor that showed significant survival benefit. Because of this, there is an urgent need to search for novel pathways in sorafenib experienced patients. This review will focus on the role of hypoxia and hypoxiainducible factor alpha(HIF-1α) in cancer development, specifically in HCC. We will discuss the biology of HIF-1α, the pathways with which it interacts, and the function of HIF-1α in HCC. Furthermore, we will review studies highlighting the relevance of HIF-1α in the clinical setting, as well as the pre-clinical data supporting its further investigation. Finally, we will conclude with a discussion of the potential role of a HIF-1α m RNA antagonist for the treatment of HCC, and hypothesize the ways in which such an inhibitor may be best utilized in the management of advanced HCC. Hypoxia plays a significant role in the development of HCC. HIF-1α is a key transcription factor involved in the hypoxic response of cancer cells. It activates transcription of genes responsible for angiogenesis, glucose metabolism, proliferation, invasion and metastasis in HCC. Its involvement in multiple, essential tumor pathways makes it an attractive potential therapeutic target in HCC.

关键词： Hypoxia Hypoxia-inducible factor alpha Hepatocellu

Frailty is independently associated with increased hospitalisation days in patients on the liver transplant waitlist

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2017年第5期23卷 899-905页

作者： Marie Sinclair Eduard Poltavskiy jennifer L Dodge jennifer C Lai Gastroenterology and Hepatology University of CaliforniaSan FranciscoCa 94143United States

AIMTo investigate the impact of physical frailty on risk of hospitalisation in cirrhotic patients on the liver transplant *** listed for liver transplantation at a single centre underwent frailty assessments using the Fried Frailty Index, consisting of grip strength, gait speed, exhaustion, weight loss, and physical activity. Clinical and biochemical data including MELD score as collected at the time of assessment. The primary outcome was number of hospitalised days per year; secondary outcomes included incidence of infection. Univariable and multivariable analysis was performed using negative binomial regression to associate baseline parameters including frailty with clinical outcomes and estimated incidence rate ratios (IRR).RESULTSOf 587 cirrhotics, 64% were male, median age (interquartile range) was 60 (53-64) years and MELD score was 15 (12-18). Median Fried Frailty Index was 2 (1-3); 31.6% were classified as frail (fried frailty ≥ 3). During 12 mo of follow-up, 43% required at least 1 hospitalisation; 38% of which involved major infection. 107/184 (58%) frail and 142/399 (36%) non-frail patients were hospitalised at least once (P < 0.001). In univariable analysis, Fried Frailty Index was associated with total hospitalisation days per year (IRR = 1.51, 95%CI: 1.28-1.77; P ≤ 0.001), which remained significant on multivariable analysis after adjustment for MELD, albumin, and gender (IRR for frailty of 1.21, 95%CI: 1.02-1.44; P = 0.03). Incidence of infection was not influenced by *** cirrhotics on the liver transplant waitlist, physical frailty is a significant predictor of hospitalisation and total hospitalised days per year, independent of liver disease severity.

关键词： Hospitalisation Infection Cirrhosis Frailty Transplantation

The Status of Acupuncture and Oriental Medicine in the United States

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2014年第4期20卷 243-249页

作者： jennifer A.M.Stone Department of Radiation Oncology Indiana University School of Medicine

Since its first mention in U.S. media in the early 1970s, the practiceof acupuncture and Oriental medicine （AOM） has grown in stature from a fringe,counter-culture movement to a valid, evidenced-based treatment option for *** the last 40 years, AOM schools and colleges have been accredited by the *** of Education, offering both masters and doctoral degree programs. Todate, forty-seven states and the District of Columbia license or certify acupuncturistsbased on competency proven through state examination or professional certificationby the National Certification Commission for Acupuncture and Oriental Medicine（NCCAOM）. As acceptance of AOM in the U.S. has increased through both theassurance of psychometrically sound certification and the education of the Americanpublic on this topic, many challenges have emerged. Problems such as theunderemployment of AOM clinicians, methodological hurdles for the investigation of mechanisms, and efficacyof acupuncture and other AOM treatment techniques have been observed. Investigative challenges also includegaps in research training as well as a dearth of the basic resources needed to conduct randomized controlledtrials （RCTs）. As AOM research has sought integration into the Western research model, problems have beenidentified in the design of AOMRCTs, and strategies for their resolution through methods such as translationalresearch have been examined. Incorporating these strategies as well as efficacy, effectiveness, and qualitativemeasures will strengthen the evidence base and thus provide clinical decision makers with more tools that canbe used to design patient treatment regimens.

关键词： acupuncture Oriental medicine status research United States challenges

Visual rating and the use of image analysis for assessing canopy density in a pecan provenance collection during leaf fall

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2023年第6期34卷 1843-1854页

作者： Cristina Pisani Clive H.Bock jennifer Randall United States Department of Agriculture−Agricultural Research Service (USDA-ARS)Southeastern Fruit and Tree Nut Research Station(SEFTNRS)ByronGA 31008USA Department of Entomology Plant Pathology and Weed ScienceNew Mexico State UniversityLas CrucesNM 88003USA

A collection representing the native range of pecan was planted at the US DA-ARS Southeastern Fruit and Tree Nut Research Station,Byron,*** collection(867 trees)is a valuable genetic resource for characterizing important horticultural *** density during leaf fall is important as the seasonal canopy dynamics provides insights to environmental cues and breeding potential of *** ability of visual raters to estimate canopy density on a subset of the provenance collection(76 trees)as an indicator of leaf shed during autumn along with image analysis values was *** canopy density using the image analysis software was less compared to visual estimates(11.9%vs 18.4%,respectively).At higher canopy densities,the raters overestimated foliage density,but overall agreement between raters and measured values was good(ρc=0.849 to 0.915),and inter-rater reliability was high(R^(2)=0.910 to 0.953).The provenance from Missouri(MOL),the northernmost provenance,had the lowest canopy density in November,and results show that the higher the latitude of the provenance,the lower the canopy *** on regression,the source provenance latitude explained 0.609 of the variation using image analysis,and0.551 to 0.640 when based on the rater estimates of canopy *** assessment of pecan canopy density due to late season leaf fall for comparing pecan genotypes provides accurate and reliable estimates and could be used in future studies of the whole provenance collection.

关键词： Carya illinoinensis Accuracy Reliability Canopy Foliage density Leaf area density Leaf area index